JP2007039300A - Laminated glass interlayer film and laminated glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interlayer film for laminated glass and a laminated glass, which are particularly excellent in weather resistance and transparency as compared with a conventional interlayer film for laminated glass and this laminated glass.
The interlayer film for laminated glass is an interlayer film for laminated glass mainly composed of an adhesive resin made of a plasticized polyvinyl acetal resin or an ethylene-vinyl acetate copolymer resin. The amount of dissolved oxygen is 0.1 ppm or less, preferably 0.01 ppm or less. Note that the intermediate film contains no antioxidant or is contained in the range of 0.2% by weight or less.
[Selection figure] None

Description

  The present invention relates to an interlayer film for laminated glass having a single layer structure or a multilayer structure particularly excellent in weather resistance and transparency, and a laminated glass using the interlayer film for laminated glass.

  Laminated glass is safe because it is difficult for objects to penetrate when subjected to external impacts, and even if it is broken by an object, glass fragments are not scattered, so it is safe. Widely used for window glass. As this type of laminated glass, a glass in which an intermediate film made of a plasticized polyvinyl acetal resin such as a polyvinyl butyral resin plasticized by a plasticizer is bonded between transparent glass plates is widely used.

  Laminated glass using an interlayer film made of this type of plasticized polyvinyl acetal resin is not sufficient in terms of weather resistance, although it is excellent in safety. In other words, when used as a window glass for vehicles such as automobiles, aircraft, buildings, etc., the interlayer film deteriorates due to sunlight and gradually turns yellow when used for a long time. As a result, the visible light transmittance of the laminated glass Decreases and the transparency deteriorates.

In order to improve this, the interlayer film for laminated glass is usually blended with an ultraviolet absorber or an antioxidant. UV absorbers and antioxidants have no improvement effect if the blending amount is too small, and conversely, if the blending amount is too large, it will precipitate on the surface of the interlayer film and reduce the adhesion and transparency with glass. Usually, it is contained in the range of 0.14 to 0.2% by weight in the intermediate film (see, for example, Japanese Patent No. 2703471). However, such conventional blending amounts are still not fully satisfactory, and there are still problems to be improved in this respect.
Japanese Patent No. 2703471

  The present invention solves the above-mentioned problems, and the object of the present invention is a laminated glass excellent in weather resistance and transparency as compared with the conventional interlayer film for laminated glass and the laminated glass. It is providing the laminated glass using the intermediate film for glass, and this intermediate film for laminated glass.

  As a result of intensive studies on conventional interlayer films for laminated glass, the present inventor has reduced the amount of dissolved oxygen in these interlayer films, thereby reducing the amount of UV absorbers and antioxidants even if the amount is reduced. It has been found that the deterioration of the interlayer film due to can be prevented. The present invention has been made based on such findings.

  That is, the invention described in claim 1 is an interlayer film for laminated glass mainly composed of an adhesive resin, wherein the dissolved oxygen content in the interlayer film is 0.1 ppm or less. It is an intermediate film for use.

  The invention according to claim 2 is the interlayer film for laminated glass according to claim 1, wherein the dissolved oxygen content is 0.01 ppm or less.

  Invention of Claim 3 does not contain antioxidant, or antioxidant is contained in the range of 0.2 weight% or less, The laminated glass of Claim 1 or 2 characterized by the above-mentioned It is an interlayer film.

  The invention according to claim 4 is characterized in that the adhesive resin is made of a plasticized polyvinyl acetal resin or an ethylene-vinyl acetate copolymer resin, and the intermediate for laminated glass according to any one of claims 1 to 3 It is a membrane.

  The invention according to claim 5 is a laminated glass characterized in that the interlayer film for laminated glass according to any one of claims 1 to 4 is bonded between transparent glass plates.

The present invention is described in detail below.
In the present invention, the resin constituting the interlayer film is an adhesive resin used in conventional interlayer films for laminated glass, such as plasticized polyvinyl acetal resin, ethylene-vinyl acetate copolymer resin, urethane elastomer resin. And vinyl chloride resin. Laminated glass using an intermediate film made of these adhesive resins has intermediate properties such as good transparency, good weather resistance, good adhesion to glass, good penetration resistance, and glass fragments are difficult to scatter. It has the basic performance required as a membrane.

  Of these, plasticized polyvinyl acetal resin is most suitable. Then, the intermediate film for laminated glasses and the laminated glass using the said plasticized polyvinyl acetal resin are demonstrated below.

  The plasticized polyvinyl acetal resin is obtained by blending a plasticizer with the polyvinyl acetal resin. As the polyvinyl acetal resin, a polyvinyl acetal resin conventionally used for an interlayer film can be used. Examples of such a polyvinyl acetal resin include an average polymerization degree of 800 to 3000 and an acetalization degree of 60 to 75 mol. % Is preferably used. Especially, the polyvinyl butyral resin of the said numerical range is suitable from the point which is excellent in the suitable adhesive force with respect to a glass plate, transparency, and a weather resistance.

  Here, if the average degree of polymerization of the resin is less than 800, the strength of the interlayer film becomes too weak, and the penetration resistance of the resulting laminated glass may be lowered. Conversely, the average degree of polymerization exceeds 3000. In some cases, the formability of the interlayer film becomes difficult, or the strength of the interlayer film becomes too strong, and the impact absorbability of the resulting laminated glass is lowered.

  Further, when the degree of acetalization of the resin is less than 60 mol%, the compatibility with the plasticizer is lowered, and it may be difficult to contain an amount of the plasticizer necessary for ensuring penetration resistance. In addition, the hygroscopicity of the interlayer film is increased and the edge of the laminated glass may become cloudy. Conversely, if the degree of acetalization exceeds 75 mol%, the strength of the interlayer film becomes too weak, Penetration resistance may be reduced.

  The average degree of polymerization and the degree of acetalization of a polyvinyl acetal resin such as a polyvinyl butyral resin are measured based on, for example, JIS K 6728 “Polyvinyl butyral test method” or nuclear magnetic resonance (NMR).

  A known method is employed to obtain the polyvinyl acetal resin. For example, a predetermined polyvinyl alcohol is used, dissolved in warm water, the obtained aqueous solution is maintained at a predetermined temperature, for example, 0 to 95 ° C., a required acid catalyst and a desired aldehyde are added, and acetal is stirred. The reaction is allowed to proceed, and then the reaction temperature is raised to ripen to complete the reaction, followed by neutralization, washing with water and drying to obtain a polyvinyl acetal resin powder.

  Here, the polyvinyl alcohol is usually obtained by saponifying polyvinyl acetate, and polyvinyl alcohol having a saponification degree of 80 to 99.8 mol% is generally used. It is preferable that the average degree of polymerization of this polyvinyl alcohol is 200-3000. If the average degree of polymerization is less than 200, the penetration resistance of the resulting laminated glass may be reduced. Conversely, if it exceeds 3000, the formability of the interlayer film becomes poor, and the rigidity of the interlayer film becomes too large. Workability may deteriorate. A more preferable average degree of polymerization is 500 to 2000.

  The average polymerization degree and saponification degree of the polyvinyl alcohol resin are measured based on, for example, JIS K 6726 “Testing method for polyvinyl alcohol”.

  The aldehyde is generally an aldehyde having 1 to 10 carbon atoms, such as n-butyraldehyde, isobutyraldehyde, n-valeraldehyde, 2-ethylbutyraldehyde, n-hexylaldehyde, n-octyl. Examples include aldehyde, n-nonyl aldehyde, n-decyl aldehyde, formaldehyde, acetaldehyde, benzaldehyde and the like. Of these, n-butyraldehyde, n-hexylaldehyde, and n-valeraldehyde are preferably used. Particularly preferred is butyraldehyde having 4 carbon atoms.

  As the plasticizer blended in the polyvinyl acetal resin, a known plasticizer generally used as a plasticizer for this kind of interlayer film can be used. For example, monobasic organic acid esters, Examples include organic plasticizers such as basic organic acid esters; phosphoric acid plasticizers such as organic phosphoric acid and organic phosphorous acid. These plasticizers may be used alone or in combination of two or more, and are used properly according to the type of the polyvinyl acetal resin in consideration of compatibility with the resin.

  Examples of monobasic organic acid ester plasticizers include glycols such as triethylene glycol, tetraethylene glycol, and tripropylene glycol, butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, heptylic acid, and n-octylic acid. Glycol esters obtained by reaction with monobasic organic acids such as 2-ethylhexylic acid, pelargonic acid (n-nonyl acid), decyl acid and the like. Among them, triethylene glycol-dicaproate, triethylene glycol-di-2-ethylbutyrate, triethylene glycol-di-n-octylate, triethylene glycol-di-2-ethylhexyl ester, etc. A monobasic organic acid ester of glycol is preferably used.

  Examples of the polybasic organic acid ester plasticizer include esters of polybasic organic acids such as adipic acid, sebacic acid, and azelaic acid with linear or branched alcohols having 4 to 8 carbon atoms. Can be mentioned. Of these, dibutyl sebacic acid ester, dioctyl azelaic acid ester, dibutyl carbitol adipic acid ester and the like are preferably used. Examples of the organic phosphate plasticizer include tributoxyethyl phosphate, isodecylphenyl phosphate, triisopropyl phosphate, and the like.

  Among these plasticizers, in particular, triethylene glycol-di-2-ethylbutyrate (3GH), triethylene glycol-di-2-ethylhexanoate (3GO), triethylene glycol-di-n-heptanoate (3G7), tetraethylene glycol-di-2-ethylhexanoate (4GO), tetraethylene glycol-di-n-heptanoate (4G7), oligoethylene glycol-di-2-ethylhexanoate (NGO), etc. Preferably used. Dibutoxyethyl adipate and dibutoxyethyl phthalate are also preferably used because they also have UV stability.

  These plasticizers are generally blended in the range of 25 to 60 parts by weight with respect to 100 parts by weight of the polyvinyl acetal resin. If it is less than 25 parts by weight, the resulting interlayer film or laminated glass may have insufficient impact absorbability. Conversely, if it exceeds 60 parts by weight, the plasticizer bleeds out and the resulting interlayer film or The optical distortion of the laminated glass may increase, or the transparency and adhesion to the glass plate may be impaired. A more preferable amount of the plasticizer is 30 to 50 parts by weight.

  As described above, as the adhesive resin constituting the interlayer film for laminated glass, the plasticized polyvinyl acetal resin such as an optimal plasticized polyvinyl butyral resin has been described. Among other adhesive resins, particularly preferable adhesive resins are , An ethylene-vinyl acetate copolymer resin. The ethylene-vinyl acetate copolymer resin preferably contains 18 to 35% by weight of a vinyl acetate component as a constituent component.

  When the content of the vinyl acetate component is increased, the transparency of the obtained interlayer film is improved, but the tensile strength is lowered. On the contrary, when the content of the vinyl acetate component is reduced, the tensile strength of the obtained interlayer film is improved, but the transparency is lowered.

  The ethylene-vinyl acetate copolymer resin preferably has a melt index (MI) of 1 to 200. If the MI is too small, the fluidity of the resulting interlayer film will be reduced, and the processability of the interlayer film will deteriorate. On the other hand, if the MI is too large, the viscosity of the resulting interlayer film decreases, the interlayer film protrudes from the end after lamination, and the film thickness decreases, and the impact resistance of the resulting laminated glass is reduced. descend. The copolymer resin includes a transparency improver (for example, benzylidene sorbitol compound or calixarene compound) or an adhesion improver (for example, silane coupling) as described in JP-A-7-2551. Agent) may be added.

  In order to prevent yellowing due to sunlight, the above-mentioned various adhesive resins constituting the intermediate film are usually blended with an ultraviolet absorber or an antioxidant. In addition, light stabilizers (such as hindered amine compounds), adhesive strength modifiers (such as alkali metal salts or alkaline earth metals of carboxylic acids), antistatic agents (such as polyoxyalkylene compounds), moisture resistance agents, colorants (blue) , Gray, bronze, green pigments or dyes) and the like may be blended.

  Here, examples of the ultraviolet absorber include ultraviolet absorbers such as malonic acid ester compounds, oxalic acid anilide compounds, benzotriazole compounds, benzophenone compounds, triazine compounds, benzoate compounds, hindered amine compounds, and the like. Among them, benzotriazole compounds such as 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) benzotriazole 2- (2′-hydroxy-3′-t-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-amylphenyl) benzotriazole 2,2-methylenebis [4- (1,1,3,3-tetramethylbutyl-6- (2H-benzotriazol-2-yl) phenol], 2- (2H-benzotriazol-2-yl)- 4,6-di-t-pentylphenol and the like are preferable.

  In addition, examples of the antioxidant include phenol-based, sulfur-based, and phosphorus-based agents. Among them, 2,6-di-t-butyl-p-cresol (BHT), butylated hydroxyanisole (BHA), 2,6-di-t-butyl-4-ethylphenol, stearyl-β- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate, 2,2'-methylenebis- (4-methyl-6-butylphenol), 2,2'-methylenebis- (4-ethyl-6-t-butylphenol) 4,4′-butylidene-bis- (3-methyl-6-tert-butylphenol), 1,1,3-tris- (2-methyl-hydroxy-5-tert-butylphenylbutane, tetrakis [methylene-3 -(3 ', 5'-butyl-4-hydroxyphenyl) propionate] methane, 1,3,3-tris- (2-methyl-4-hydroxy-5-tert-butylphenol) Butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, bis (3,3′-tert-butylphenol) butyric acid ) Glycol esters are preferred.

  When the blending amount is increased, the ultraviolet absorber and the antioxidant are deposited on the surface of the intermediate film and the adhesion and transparency to the glass plate are lowered. Although it mix | blends in 14 to 0.2 weight%, even if mix | blended in the quantity smaller than that, the weather resistance equivalent to or more than before can be acquired.

  The total film thickness of the interlayer film for laminated glass of the present invention is not particularly limited, and in consideration of the minimum necessary penetration resistance and weather resistance as a laminated glass, a practically transparent interlayer film for laminated glass is practically used. In general, a film thickness range of 0.3 to 1.6 mm is preferable. In particular, a film thickness range of 0.7 to 1.6 mm is preferable. Further, not only an intermediate film having a single layer structure formed of a single resin film, but also an intermediate film having a multilayer structure in which two or more resin films are laminated for the purpose of improving sound insulation, for example.

  The adhesive resin, for example, polyvinyl acetal resin, plasticizer and various compounding agents to be blended as necessary are kneaded using an extruder, plastograph, kneader, Banbury mixer, calendar roll, etc., and this is an extrusion method. It can be obtained by a method of forming a sheet by a normal film forming method such as a calendar method or a press method.

  An intermediate film having a multilayer structure can be manufactured by a method in which a plurality of resin films formed by the above method are stacked and integrated by heating and pressing. Moreover, the resin compound for film formation can be manufactured by the method of integrally forming a film by the multilayer extrusion method. Further, as another method, a plurality of resin films can be laminated between two transparent glass plates and integrated by heating and pressurizing, and can be produced by a method of forming a film simultaneously with the production of laminated glass. .

  In the present invention, it is necessary that the amount of dissolved oxygen in the intermediate film is 0.1 ppm or less. In particular, it is preferably 0.01 ppm or less. Here, the amount of dissolved oxygen in the intermediate film was measured using a SCAN mode measurement (measurement temperature: 30 ° C. to 250 ° C.) using the TDS-MS (WA1000S / W, manufactured by Electronic Science Co., Ltd.). ° C, heating rate: 1 ° C / min). The amount of dissolved oxygen is calculated from the ratio of m / z = 16 and m / z = 32 by mass chromatography for the distillate from the intermediate film.

  Various methods are employed to reduce the dissolved oxygen content in the interlayer film to 0.1 ppm or less. For example, a raw material containing dissolved oxygen, such as an adhesive resin or plasticizer that constitutes an intermediate film, or a resin compound for film formation containing these raw materials is dissolved and diluted in an appropriate solvent, and nitrogen gas is sufficiently added to the solution. A method is adopted in which the air present in the solution is sufficiently replaced with an inert gas such as nitrogen gas, and the residual oxygen is removed by performing a vacuum exhaust treatment.

  When an oxygen gas adsorbing raw material such as a carbon compound or metal fine particles is blended, a pretreatment such as a heat treatment in an inert gas atmosphere such as nitrogen is required in advance. In addition, when using a raw material that generates active oxygen species when irradiated with ultraviolet rays, such as titanium oxide fine particles and zinc oxide fine particles, the surface of the fine particles must be coated with a substance such as silica. Moreover, it is necessary to select a surfactant having a low oxygen adsorptivity as a surfactant used for dispersing various organic fillers and inorganic fillers. In addition, when using a film forming apparatus that easily generates oxygen radicals, such as an extrusion film forming apparatus, an additive that traps oxygen radicals is effective.

  If the amount of dissolved oxygen in the interlayer exceeds 0.1 ppm, the laminated glass is exposed to sunlight for a long period of time, resulting in yellowing of the interlayer. As a result, the visible light transmittance of the laminated glass is lowered and becomes transparent. In order to prevent this, it is necessary to add an ultraviolet absorber or an antioxidant in the range of 0.14 to 0.2% by weight. In addition, when a ultraviolet absorber and antioxidant are mix | blended in the range exceeding 0.2 weight%, an ultraviolet absorber and antioxidant will precipitate on the surface of an intermediate film, and adhesiveness with glass and transparency will fall.

  The laminated glass of this invention can be manufactured by the method similar to the manufacturing method of a normal laminated glass. For example, the interlayer film for laminated glass having the single layer structure or the multilayer structure described above is sandwiched between at least two transparent glass plates, and this is handled through a pressing roll or put in a rubber bag and sucked under reduced pressure, and glass While pre-adhering at about 70 to 110 ° C. while deaerating air remaining between the plate and the interlayer film, a laminated body is formed. Then, the degassed laminated body is put in an autoclave or pressed, and about 120 It is manufactured by performing main bonding at a pressure of about 1 to 1.5 MPa at ˜150 ° C.

  In addition, as a transparent glass plate, the transparent glass plate generally used can be used. Examples of such transparent glass plates include, for example, float plate glass, heat ray absorbing glass, polished plate glass, mold plate glass, netted plate glass, wire-containing plate glass, and other inorganic glasses: organic glass plates such as polycarbonate plates and polymethyl methacrylate plates. Is mentioned. These glass plates may be used independently and two or more types may be used together. In addition, the thickness of these glass plates should just be selected suitably by a use, and is not specifically limited.

  In the interlayer film for laminated glass of the present invention, the amount of dissolved oxygen in the interlayer film is 0.1% by weight or less, and the laminated glass of the present invention obtained using such an interlayer film is oxidized into the interlayer film. Even if it contains no inhibitor, or contains an antioxidant in a smaller amount than before, even if it is used over a long period of time, the interlayer film does not deteriorate due to sunlight and gradually turns yellow. No visible light transmittance is reduced, high optical characteristics can be maintained, and excellent transparency is maintained.

In the present invention, the weather resistance was evaluated using a sunshine carbon arc lamp type weather resistance tester (“S80B” manufactured by Suga Test Instruments Co., Ltd.), and irradiated for 300 hours at a sample surface irradiance of 255 W / m ² . The humidity was 60% and the temperature of the black panel was 63 ° C. No spraying was performed.
Regarding the laminated glass before and after the weather resistance test, the difference in visible light transmittance (Tv) according to JIS R 3106, that is, the change rate ΔTv = Tv ₂ (after irradiation) −Tv ₁ (before irradiation) is 1% or less, JIS Difference in yellowness (YI) due to K 7105, that is, rate of change (yellowing degree) ΔYI = YI ₂ (after irradiation) −YI ₁ (before irradiation) is 1 or less, which is superior in weather resistance compared to the conventional case. An interlayer film for laminated glass and laminated glass can be obtained.

  In addition, the interlayer film for laminated glass of the present invention has a weather resistance equivalent to or better than that of a conventional interlayer film even when a lesser amount of UV absorber or antioxidant is blended in the interlayer film. Therefore, it contributes to the cost reduction of ultraviolet absorbers and antioxidants.

  Therefore, the laminated glass using the interlayer film for laminated glass of the present invention is used for, for example, an automobile windshield, a side glass, a rear glass, a roof glass; a glass part of a vehicle such as an aircraft or a train; a window glass of a building; . In particular, since a good field of view can be maintained for a long period of time, it is preferably used for a windshield and a front side glass of an automobile.

  Hereinafter, the present invention will be described in detail by giving specific examples of the present invention. The present invention is not limited to these examples.

(1) Preparation of plasticizer solution Dissolve the UV absorber in diethylene glycol monoethyl ether (trade name “Seafosol” manufactured by Nippon Shokubai Co., Ltd.), which is a plasticizer used as a solvent, so as to have a concentration of 1.1% by weight. It was. Thereafter, nitrogen gas was sufficiently passed through the solution to replace the air present in the solution with nitrogen gas, and vacuum evacuation was further performed. By this operation, a plasticizer solution from which residual oxygen was sufficiently removed was prepared.

(2) Production of interlayer film for laminated glass In a sealed heat-resistant container with an exhaust device, 100 parts by weight of polyvinyl butyral resin and 10 parts by weight of triethylene glycol-di-2-ethylhexanoate as a plasticizer are placed and stirred in a sealed state. After mixing, the sealed heat-resistant container was heated to 200 ° C. to melt the polyvinyl butyral resin. Next, nitrogen gas was sufficiently passed while stirring was continued to replace the air present in the molten resin with nitrogen gas, and vacuum evacuation was performed. By this operation, a resin composition from which residual oxygen was sufficiently removed was prepared.

  Then, after cooling the sealed heat-resistant container to room temperature, this sealed heat-resistant container is transferred into a glove box filled with nitrogen, and the container is opened. The plasticizer solution prepared in (1) above is described in Table 1. The mixture was added to a proper ratio and heated to 150 ° C. An interlayer film for laminated glass having an average film thickness of 0.8 mm was produced by casting the composition in the molten state.

(3) Measurement of dissolved oxygen in interlayer film for laminated glass The obtained interlayer film for laminated glass was measured by SCAN mode (measurement temperature: 30 ° C.) using TDS-MS (WA1000S / W, manufactured by Electronic Science Co., Ltd.). ˜250 ° C., heating rate: 1 ° C./min). The amount of dissolved oxygen was calculated from the ratio of m / z = 16 and m / z = 32 by mass chromatography for the distillate from the intermediate film. As a result, the dissolved oxygen content in the interlayer film was 0.0076 ppm.

(4) Production of laminated glass The obtained interlayer film for laminated glass was sandwiched between two transparent float glass plates (length 30 cm × width 30 cm × thickness 2.5 mm) and placed in a rubber bag. After degassing for 20 minutes at a vacuum degree of .6 kPa, it was transferred to an oven while being degassed, and further vacuum pressed while being held at 90 ° C. for 30 minutes. The laminated glass preliminarily pressure-bonded in this manner was pressure-bonded for 20 minutes in an air-type autoclave under conditions of 135 ° C. and a pressure of 1.2 MPa to produce a transparent laminated glass.

(5) Weather resistance test of laminated glass The obtained laminated glass was cut into a width of 5 cm and a length of 10 cm to obtain a test piece. The test piece was irradiated with a sunshine carbon arc lamp type weather resistance tester (“S80B” manufactured by Suga Test Instruments Co., Ltd.) at a sample surface irradiance of 255 W / m ² for 300 hours. The panel temperature was 63 ° C. No spraying was performed.

(Comparative Example 1)
(10) Preparation of plasticizer solution As in Example 1, diethylene glycol monoethyl ether (trade name “manufactured by Nippon Shokubai Co., Ltd.”), which is a plasticizer used as a solvent, was used so that the concentration of the ultraviolet absorber was 1.1% by weight. A plasticizer solution was prepared by dissolving in seafosol ").

(20) Preparation of interlayer film for laminated glass 100 parts by weight of polyvinyl butyral resin, 10 parts by weight of triethylene glycol-di-2-ethylhexanoate as a plasticizer, and UV absorption of the plasticizer solution prepared in (10) above It added and mixed so that the ratio of an agent might become the ratio of Table 1, and it heated to 150 degreeC. An interlayer film for laminated glass having an average film thickness of 0.8 mm was produced by casting the composition in the molten state.

(30) Measurement of dissolved oxygen in interlayer film for laminated glass The amount of dissolved oxygen in the interlayer film was measured in the same manner as in Example 1. As a result, the amount of dissolved oxygen was 0.2001 ppm.

(40) Production of laminated glass Using the laminated glass produced in (40) above, a transparent laminated glass was produced in the same manner as in Example 1.

(Evaluation)
For the laminated glass obtained in Example 1 and Comparative Example 1, the difference in visible light transmittance (Tv), that is, the change rate ΔTv = Tv ₂ (after irradiation) −Tv ₁ (before irradiation), and the change rate ( The difference in yellowing degree (ΔYI), that is, ΔYI = YI ₂ (after irradiation) −YI ₁ (before irradiation) was measured, and the results are shown in Table 1.

  In addition, visible light transmittance ((DELTA) Tv) uses the direct-write spectrophotometer ("U-4000" by Hitachi, Ltd.) about the laminated glass before and behind the said weather resistance test, JISR3106 "transmittance of plate glass * In accordance with “Test method for reflectance, emissivity, and solar radiation acquisition rate”, the visible light transmittance (Tv) at a wavelength of 380 to 780 nm was measured and calculated. Moreover, yellowing degree ((DELTA) YI) is based on JISK7105 "the optical characteristic test method of a plastics" about the laminated glass before and behind the said weather resistance test using a photoelectric colorimeter (conforming to JISZ8722), The yellowness (YI) was measured and calculated.

Claims (5)

  An interlayer film for laminated glass comprising an adhesive resin as a main component, wherein the amount of dissolved oxygen in the interlayer film is 0.1 ppm or less.   The interlayer film for laminated glass according to claim 1, wherein the dissolved oxygen content is 0.01 ppm or less.   The interlayer film for laminated glass according to claim 1 or 2, wherein the interlayer film does not contain an antioxidant or is contained in an amount of 0.2% by weight or less.   The interlayer film for laminated glass according to any one of claims 1 to 3, wherein the adhesive resin is made of a plasticized polyvinyl acetal resin or an ethylene-vinyl acetate copolymer resin. A laminated glass, wherein the interlayer film for laminated glass according to any one of claims 1 to 4 is bonded between transparent glass plates.